Various filter units have been developed in the past for filtering fluid passing therethrough. One such type of filter unit includes cylindrical filter cartridges which are mounted longitudinally within a filter unit's housing, for instance, in a circular array. Because the filter cartridges are typically open-ended, it is necessary to seal the open ends of each filter cartridge such that fluid flows through an associated filter medium positioned intermediate the ends of the filter cartridge, thereby achieving proper filtering operation. For proper sealing of the filter cartridges, it is desirable to orient them in proper alignment relative to each other and relative to the housing of the filter unit. For various reasons (e.g., manufacturing imprecision), the filter cartridges have slightly different lengths, and, as a result, it has been difficult to properly and positively align and thereby seal the filter cartridges in a quick and efficient manner.
A number of devices have been proposed for aligning and/or sealing filter cartridges mounted within a housing of a filter unit (see, for instance, U.S. Pat. Nos. 2,904,184, 3,319,793, 4,052,317, 4,248,714, 4,428,838, 4,442,004, Re. 31,966, 4,731,184, 4,946,588 and 5,399,264). It is, however, believed that none of the devices disclosed in the foregoing patents is adapted to properly and positively hold, seal and/or align associated filter cartridges in a quick and efficient manner. As a result, there is a need for a filter cartridge holding device adapted for performing these functions in a quick and efficient manner.